A complete model of E2PROM memory cells for circuit simulations

E²PROM memory devices are widely used in embedded applications. For an efficient design flow, a correct modeling of these memory cells in every operation condition becomes more and more important, especially due to power consumption limitations. Although E²PROM cells have being used for a long time, very few compact models have been developed. Here, we present a complete compact model based on an original procedure to calculate the floating gate potential in DC conditions, without the need of any capacitive coupling coefficient. This model is designed as a modular structure, so to simplify program/erase and reliability simulations. Program/erase and leakage currents are included by means of simple voltage-controlled current sources implementing their analytical expression. It can be used to simulate memory cells both during read operation (DC conditions) and during program and erase (transient conditions) giving always very accurate results. We show also that, provided there are good descriptions of degradation mechanisms, the same model can be used also for reliability simulations, predicting charge loss due to tunnel oxide degradation.